1. Field of the Invention
The present invention relates to a sheet processing apparatus, a control method therefor, and a storage medium.
2. Description of the Related Art
For sheet processing apparatuses that stack a large number of sheets, there has been demand for the ability to discharge and align the sheets with a high degree of accuracy. Japanese Patent Laid-Open No. 2006-206331 suggests a sheet alignment process in which alignment members are provided on a stack tray, and sheets are piled up in such a manner that the positions of edge surfaces of the sheets parallel to a sheet discharge direction are aligned by the alignment members coming into and out of contact with the edge surfaces of the sheets.
However, the above conventional technique has the following problems. For example, although the above conventional technique places emphasis on the alignment performance and applies the alignment process at the time of discharge, there are cases where it is not necessary to place emphasis on the alignment performance for output materials depending on the purpose of a user and the type of a job. For example, even when the user wants to check pages that are being output to a discharge destination in the middle of the output, constant operations of an alignment process unit do not allow the user to easily pick up the output materials in the middle of the output, unlike when pages are discharged to a sheet processing apparatus with no alignment process.
The types of jobs that do not place emphasis on the alignment performance compared to other types of jobs are, for example, rush printing (interrupt printing) and a sample printing job. According to these types of printing, there are cases where the stacking performance is not required because output materials are expected to be immediately picked up from a discharge tray. Furthermore, the alignment process may cause friction depending on the type of mediums used in certain jobs; therefore, in the case where the alignment process is not desirable for those jobs, it is required to perform control so as not to apply the alignment process only to those jobs.
However, according to the above conventional technique, whether or not to apply the alignment process on a per-job basis cannot be set, and therefore it is necessary for the user to pre-set a discharge tray on which the alignment process is not executed, or it is necessary to output sheets on the premise that the output sheets will be subject to the friction. Furthermore, in the alignment process, operational noise occurs while the alignment process unit is in operation. For example, in the case where the sheet processing apparatus is operating in a silent mode in which this operational noise is undesirable, it may be appreciated if the alignment process is not applied to give priority to silence. As described above, although there are cases where the alignment process is undesirable depending on the purpose, conventional configurations do not control the operations of the alignment process in accordance with the types or purposes of jobs.